The present invention relates to a passenger-side air bag apparatus, particularly, relates to a passenger-side air bag apparatus wherein an air bag module is placed within an instrument panel installed forward of a passenger seat and the air bag module can be easily attached and removed.
A passenger-side air bag apparatus of a vehicle has an air bag module which houses an inflator and an air bag in a module case. The air bag module is supported by a structural member such as a steering hanger beam across an instrument panel and placed within the instrument panel installed forward of a passenger seat. An air bag lid is configured to be broken and open by inflation of the air bag. The air bag lid is mounted on the opening portion of the module case to cover the air bag in the module case, or molded in one piece on the top wall of the instrument panel installed forward of the passenger seat in advance.
With the air bag module having the air bag lid mounted on the opening portion of the module case, the air bag module is inserted from above into an opening for mounting on the top wall of the instrument panel installed forward of the passenger seat. The lower portion of the module case is fixed detachably via tightening means on the structural member such as a steering hanger beam. A tightening means includes a bracket, a stud bolt, a nut and the like. The edge of the air bag lid on the top end of the module case is locked on the periphery of the opening for mounting.
With the air bag lid molded in one piece on the top wall of the instrument panel, in a state in which the opening portion of the module case is opposed to the inner surface of the air bag lid, the fore-and-aft part in the vicinity of the opening portion is fixed in advance detachably via the tightening means on the inner surface of the instrument panel. After the instrument panel is mounted on a car body, the lower portion of the module case is fixed detachably via the tightening means on the structural member such as a steering hanger beam.
There is a problem about the passenger-side air bag apparatus having the air bag module with the air bag lid. Specifically speaking, the air bag lid on the top end of the module case inserted into the opening for mounting on the top wall of the instrument panel is exposed at the outer surface of the instrument panel. Therefore, togetherness of the instrument panel is impaired and the instrument panel is defiled.
The passenger-side air bag apparatus which has the air bag lid molded in one piece on the top wall of the instrument panel in advance, is free from the above-described problem. However, There is another problem about this type of passenger-side air bag apparatus. Specifically speaking, when the air bag module is attached to and removed from the instrument panel to perform a check or maintenance thereon, the attaching and removing operation requires a multitude of man-hours. Front and rear tightening means fix the front and rear of the upper portion of the module case to the inner surface of the instrument panel. When the air bag module of this type of passenger-side air bag apparatus is attached to and removed from the instrument panel, the front and rear tightening means are to be attached and removed, e.g., via an opening portion for a glove box of the instrument panel. In the state in which the instrument panel is mounted on a car body as a practical matter, various structures such as a steering hanger beam, a dashboard and the like interfere with the operation. Therefore, the front tightening means of the upper portion of the module case cannot be attached and removed in such state. As a result, to attach and remove the air bag module, the instrument panel must be removed from the car body temporarily and a multitude of man-hours is needed.
Therefore, an object of the present invention is to provide a passenger-side air bag apparatus having an air bag module which can be easily attached and removed without defiling an instrument panel and without attaching and removing the instrument panel.
To achieve the above-mentioned object, a passenger-side air bag apparatus according to the present invention comprises:
an air bag lid molded in one piece with a top wall part of an instrument panel forward of a passenger seat in a vehicle; and
an air bag module capable of passing through a glove box opening portion formed on a side wall part of the instrument panel forward of the passenger seat;
the air bag module being disposed within the instrument panel in a state in which an opening portion of the top end of a module case housing an inflator and an air bag faces the inner surface of the air bag lid, a lower portion of the module case is fixed detachably to a structural member laid across the instrument panel via a lower portion fastening mechanism capable of being operatively manipulated via the glove box opening portion, and an upper portion of the module case is fixed detachably to the top wall part of the instrument panel via an upper locking mechanism also capable of being operatively manipulated via the glove box opening portion.
The air bag module of a passenger-side air bag apparatus according to the present invention may be readily removed to the outside of the instrument panel to perform a check or maintenance thereon. First, a tool such as an impact wrench releases the lower portion tightening means. Next, the lower portion of the module case is detached from the structural member by manual work via the glove box opening portion. Subsequently, the module case is moved in a predetermined direction so that the upper locking mechanism is released and the upper portion of the module case is detached from the top wall part of the instrument panel. The whole of the air bag module is then taken out through the glove box opening portion to the outside of the instrument panel. After the check and maintenance for the air bag module is performed, a reverse procedure is carried out for re-installing the air bag module. The upper portion of the module case is locked on the top wall part of the instrument panel by the upper locking mechanism. The lower portion of the module case is fixed to a support member via the lower portion locking mechanism.
In regard to a passenger-side air bag apparatus according to the present invention, it is preferable that the upper locking mechanism comprises a front locking means for locking the front of the upper portion of the module case and a rear locking means for locking the rear of the upper portion of the module case. In the event of a collision, the air bag breaks the air bag lid when the air bag is inflated and expands toward the passenger seat of the car body. The front and rear locking means reliably prevent the module case from moving to tilt in a fore-and-aft direction due to reaction of inflating and expanding of the air bag.
In regard to a passenger-side air bag apparatus according to the present invention, it is preferable that the upper locking mechanism comprises a front locking means for locking the front of the upper portion of the module case and a rear locking means for detachably fixing the rear of the upper portion of the module case to the top wall part of the instrument panel, the rear locking means is capable of being manipulated via the glove box opening portion. In the event of collision, the air bag breaks the air bag lid when the air bag is inflated and expands toward the passenger seat of the car body. The front locking means and the rear locking means further reliably prevent the module case from moving to tilt in a fore-and-aft direction due to reaction of inflating and expanding of the air bag.